Switch protecting device

ABSTRACT

A combined switch-protecting and safety device has safety fuses which can be introduced separately into openings provided in a front wall of a casing, while a rear wall extending parallel to the front wall serves as a supporting plate for switch protective means the various parts of which are mounted on the outer side of the plate.

United States Patent [72) Inventor Kurt Tage Lennart Bergman Sundsvall, Sweden {21 Appl. No. 734,484

[22] Filed June 4, 1968 (45] Patented Sept. 14, 1971 [73] Assignee David 0. Hagglund Stockholm, Sweden [32] Priority June 5, 1967 [33] Sweden [54] SWITCH PROTECTING DEVICE 1 Claim, 8 Drawing Figs.

[52] US. Cl 337/8 [51] Int. Cl "01h 85/56 [50] Field of Search 337/5, 6, 7, 8.9, 211, 212, 2l3, 2l8; 335/126, 142; 200/3 [56] References Cited UNITED STATES PATENTS 2,950,370 8/l960 Swain 337/7 1,554,459 9/1925 Norquist 337/9 X 3,284,598 11/1966 George et a1. 337/211 3,202,788 8/1965 George ,37/213 X 2,949,516 8/1960 Edmunds.... 337/6 2,919,324 12/1959 Schussler 335/126 X FOREIGN PATENTS 6,602,012 9/1966 Netherlands 337/ 7 464,329 12/ 1 968 Switzerland 337/8 Primary Examiner-Remard A. Gilheany Assistant Examiner-Dewitt M. Morgan Attorney-Richards & Geier ABSTRACT: A combined switch-protecting and safety device has safety fuses which can be introduced separately into openings provided in a front wall of a casing, while a rear wall extending parallel to the front wall serves as a supporting plate for switch protective means the various parts of which are mounted on the outer side of the plate.

PATENIEB 5m 4 m1 SHEET 1 0F 5 INVENTOR lulu mes LENNART mmcmm ATTORNEYS PATENTED SEN 4 l97| saw 2 [IF 5 INVENTOR xuwr ucz LENNART nzncm ATTORNEYS SHEET 3 [IF 5 PAI-ENIED YSEPI 41971 PATENTEU SEP! 4 ml INVENTOR KURT TAGE LENNART BERGHAN Anomzvs PATENTED SEN 4 I971 SHEET 5 0F 5 l N VEN TOR X ur/ Eye 1 emmm/beyma switch-protecting and safety device having fuses which can be introduced into the casing of the device. Installations for electric power-distribution which are now in use have supporting plates upon which the various parts are mounted, whereby fuses and switches are placed next to each other upon the front surface of the plate, possibly along with various signaling and auxiliary devices. This placing of the various parts constituting a single aggregate results in a confused arrangement of devices and conducting wires extending between them which is difficult to supervise; it also involves 15 high-fixing costs and provides difiiculties when looking for a damaged part and when removing such part damaged, for example, as the result of a short circuit.

" An object of the present invention is to eliminate these drawbacks of prior art installations.

Other objects of the present invention will become apparent in the course of the following specification.

' In the accomplishment of the objectives of the present invention it was founddesirable to provide a combined switchprotecting and safety device having a front wall provided with 25 present invention has the advantages of an orderly arrange- 30, v v I chambers for the last three fuse holders 76, 78 and 89 extendment, concealed switch protection, simple mounting, easy acc essibility during operation or for inspection, as well as great operational safety.

" The invention will appear more clearly from the following detailed description when taken in connection with the ac companying drawings, showing by way of example only, a preferred embodiment of the inventive idea.

' In the drawings:

FIG. 1 is a top view, partly in section, of the device of the present invention with the fuses removed.

FIG. 2 is a rear view of the device, partly in section.

FIG. 3 corresponds to FIG. 1 but shows the main parts of the switch safety means as being removed from the casing.

FIG. 4 is a side view of a fuse holder on an enlarged scale.

FIGS. 4a and 4b are diagrams illustrating the electrical connections.

' FIG. 5 is a rear view of the fuse holder of FIG. 4.

FIG. 6 is a front view of the same fuse holder.

The combined switch-protecting and safety device shown in FIG. 1 includes a carrying casing 10 made preferably of a hardenable synthetic material, such as melamine resin. In the example the casing illustrated is divided into six separate spaces 12, each of which is intended to receive a separate fuse holder 14. The fuse holders 14 are introduced from the front 55 into the casing through openings 18 provided in the front wall 16 thereof.

As shown in FIGS. 4, 5 and 6, the fuse holder 14 has a sidewall carrying two contacts 20 and 22 located one above the other and adapted to be electrically connected by contacts 60 24 and 26 located within the holder in a manner hereinafter described. The contacts 24 and 26 can establish connection with one or two safety fuses 28 and 30 which are located one above the other as soon as the fuses have been introduced from the side into the fuse holder. The holder carries a stop 31 65 located between the fuses. In order to insert the fuse holder 14 into the casing 10, the front side of the holder has a handgrip 32 provided with openings 34 used to observe the signals of the fuses provided with small plates for that purpose.

The rear wall 36 of the casing 10 (FIG. 1) carries contacts 70 lation, since one side of the front wall 16 of the casing is provided with a hinge 42 while the other side has a lock or bolt 44.

The front portion 46 of the fuse holder is carefully sealingly fitted into the opening 18 of the casing so as to avoid penetra tion of moist and/or salt-carrying air into the casing'which; could produce deposits upon the insulating parts of the fuse holder.

Obviously, the illustrated fuse holder can be changed in that the fuses with melting wires can be replaced by electromechanical safety devices or excess current relays.

The contacts 38 upon the rear wall 36 of the casing 10 are also connected to contacts 48 and 50 extending through the wall 36 and fixed thereon. These two contacts 48 and 50 are enclosed by a wall 52 constituting a separate part made of an insulating material and forming a switching-chamber 54 with an opening 56 (FIG. 2). An actuating rod 58 which is movable in the axial direction, extends through the chamber 54 and carries a contact bridge 60. When the rod 58 is actuated by an electromagnet 62, the contacts 48 and 50 will be interconnected by the contact 60. The switching chamber 54 is covered from the outside by a cover 64 which also serves as a cover for other switching chamberssim ilar tothe chamber 54 and containing corresponding contacts connected in series with the two fuse holders 66 and 68 located next "to the fuse holder 15 (FIG. 1). The cover 64 has openings 70 and 72 (FIG. 2) containing spark quenching sheets 74 for the quenching of arcs which could occur during operation when opening the contacts 48, and 50. There are no switching ing in one row with the'otherfuse holders (FIG. 1 It is ap parent that the contacts 24, 26 which are engaged by the fuse contacts, are connected by wiring with thetwo contacts 20,22 which work together with the contacts 38 in casing 10'. The contact 24 can be electrically connected with the contact 20 or with the contact 22, while the contact 26 'is connectedfwith the contact 22 or 20. The contact 24 connects one of the-two contacts 20 or 22 with the lower contact of the fuse 28 or 30. The contact 26 interconnects the two upper contacts of the fuses 28 and 30. The connection of the fuses 2 8and 30 with the switch contacts 48, 60 and 50 can be carried out at will depending upon existing requirements and canbe'different depending upon the desired circuit. The fuses can be connected in series with the switch contacts or can be completely separated electrically from the circuits of these switch contacts.

In FIG. 2 the contacts 48, 50 and 60 are shown as closing contacts. However, it is also obviously possibleto make some of the other contacts as opening contacts, such as thecontacts 82. The contacts 82-90 are included in actuating and signaling circuits and therefore are made substantially weaker than the three contact groups at the outer end of the actuating rod 58. While the electromagnet when energized moves the rod 58 toward it, the return movement of the rod 58"into its initial position is effected by a coiled spring 92 one end of whichis attached to a disc 94 fixed to the rod 58, while the other end of the spring engages the casing of the electromagnet 62.

FIG. 3 shows the individual switch safety parts after the removal of the casing 10. In the casing remain the contacts 48 and 50 which are fixed to the casing outside of the space 12', as well as fixed contacts 96, 98 and 100, 102 as well as contacts 104-112 belonging to the contact devices 182-90. The constructive unit which is removable fromthe casing includes the electromagnet 62, the actuating rod 58 and the supporting plate 114 for these parts. Thus in caseof any damage or improper operation, the contacts fixed to the casing 10 can be conveniently repaired or exchanged. After the removal of the electromagnet 62 with the actuating rod 58, the movable contacts 60 and 116-128 also become easily accessible and, if necessary, can be replaced. The switching chamber 52 is attached to the casing 10 by means of a fastener or stop spring (not shown) and it is necessary to remove the chamber 52 before the electromagnet with the actuating rod can be withdrawn. The cover of the chamber 52 contains quenching sheets 74 which are fixed in groups to a frame 130 made of a plastic material.

Some of the fixed contacts 48, 50 and 96-112 which are fixed in the casing and which are not connected to the contact 38 for the connection of the fuse holders 1'5, 66, 68 and 76-80, are attached to separate conducting wires 40, which connect the various parts of the combined switch-protecting and safety device with the other devices and contact clamps of an apparatus, for example a switchboard, a meter board, an installation board etc., to which the combined switch-protecting and safety device of the present invention belongs; the device can be placed inside another suitable container, and then the hinge 42 can be conveniently used to swing the device in and out, to facilitate constructional operations or repairs.

It is apparent that the example described above has been given solely by way of illustration and not by way of limitation and that it is capable of many variations and modifications within the scope of the present invention.

What is claimed is:

l. A combined switch-protecting and safety device comprising a casing having a front wall, a rear wall extending parallel to said front wall, and a plurality of partitions between said walls forming separate spaces, said front wall having a plurality of openings, at separatefuse holder tightly fitting 'in each opening and extending in a separate space, a separate sidewall carried by each fuse holder, contacts carried by said side walls, other contacts connected with the first-mentioned contacts, safety fuses connected with the second-mentioned contacts, yet other contacts carried by the side of said rear wall facing said front wall and adapted to be engaged by the firstmentioned contacts, yet other contacts constituting switch elements connected with the third-mentioned contacts and located upon the outer side of the rear wall, a rod, an electromagnet actuating said rod, and at least one contact carried by said rod and adapted to interconnect the fourth-mentioned contacts and providea switch connection, said rod and said electromagnet being removably mounted upon said rear wall, whereby removal of said rod' and said electromagnet the con tacts carried by the rear wall are available for inspection and repairs. v 

1. A combined switch-protecting and safety device comprising a casing having a front wall, a rear wall extending parallel to said front wall, and a plurality of partitions between said walls, forming separate spaces, said front wall having a plurality of openings, a separate fuse holder tightly fitting in each opening and extending in a separate space, a separate side wall carried by each fuse holder, contacts carried by said side walls, other contacts connected with the first-mentioned contacts, safety fuses connected with the second-mentioned contacts, yet other contacts carried by the side of said rear wall facing said front wall and adapted to be engaged by the first-mentioned contacts, yet other contacts constituting switch elements connected with the third-mentioned contacts and located upon the outer side of the rear wall, a rod, an electromagnet actuating said rod, and at least one contact carried by said rod and adapted to interconnect the fourth-mentioned contacts and provide a switch connection, said rod and said electromagnet being removably mounted upon said rear wall, whereby removal of said rod and said electromagnet the contacts carried by the rear wall are available for inspection and repairs. 